I don't know. They kind of layed his behavior out in a way that it could be viewed from either perspective. It was like he coming clean with his family as a means of saying goodbye. But was it a goodbye because he's now become a full time terrorist, or he's expecting to die in an explosion, or is it a goodbye because he intends to move on with Carrie who just understands him more than they will ever be able too. To me it could've been read either way, and I'm positive that was done intentionally.

It would've looked more clear had Brody been the one to call Carrie away, and not the other way around. His "that's weird, someone moved my car." line, was intentionally misleading. Would it have changed things had we not known that info. If the explosion just happened, and then after the fact we learned with Saul that it appeared to come from Brody's car. It was as if that line were placed there to explicitly tell the audience that either there's someone else participating, or that he's trying to convince Carrie that there's someone else participating. Otherwise what's the point.

He wouldn't tell his family that if he was still a terrorist because he wouldn't run the risk of himself being exposed if he still had future terrorist plans in mind. He might trust them enough and risk telling them if he was done with that life but I don't see him telling them if he still had plans.